The sump im loking at only has 1 spot for the water to go into the sump fron the tank will this be a problem?

All sumps are designed this way. Water enters at one spot and is returned via another spot.

i know on the one i have now there are 2 bulk heads on the lid so each over flow has its own hook up i am just worried that with one when the water is comeing down to where i tee it off for the two line to drain will it cause a back up in the over flow